Table 1.
Characteristics of included studies.
| References | Study design | Sample size (M/F) |
Age | Population | Withdrawal duration (hour) | post-administration waiting time (min) | Intervention dose | Administration route | Outcome measure |
|---|---|---|---|---|---|---|---|---|---|
| Amor et al. (8) | RCT crossover |
N = 24 (24/0) |
16.9 | athletes | 24 | 30 | 3 mg/kg | Capsule | SRT (RT) ↑; CRT (RT) →; Stroop Test (RT) ↑; Stroop Test (AC) ↑ |
| Barry et al. (17) | RCT crossover |
N = 24 12/12 |
10.6 | ordinary people | 4 | 38.1 | NR | Capsule | Go/No Go (RT) ↑; Go/No Go (AC) ↑ |
| Bougrine et al. (39) | RCT crossover |
N = 15 (0/15) |
16.3 | athletes | 24 | 60 | 6 mg/kg | Capsule | SRT (RT) ↑; Attention Test (AC) ↑ |
| Bougrine et al. (15) | RCT crossover |
N = 14 (0/14) |
17.4 | athletes | 24 | 60 | 6 mg/kg | Capsule | SRT (RT) ↑; CRT (RT) ↑; Attention Test (AC) ↑; MRT (RT) ↑; MRT (AC)→ |
| Duncan et al. (35) | RCT crossover |
N = 13 (6/7) |
20 | ordinary people | 48 | 60 | 3 mg/kg | Liquid | CAT (AC) ↑ |
| Feng et al. (7) | RCT crossover |
N = 15 (15/0) |
20 | athletes | 24 | 45 | 5 mg/kg | tablet | Anticipation Accuracy (AC) ↑; SRT (RT) ↑ |
| Jordan et al. (34) | RCT crossover |
N = 17 (17/0) |
14.1 | athletes | 24 | 60 | 6 mg/kg | Capsule | Dominant Side (RT) → |
| Kammerer et al. (21) | RCT crossover |
N = 14 (14/0) |
20 | soldier | 5 | 45 | 1.18 mg/kg | Liquid | FAT (AC) →; DS (AC) → |
| Nana et al. (33) | RCT crossover |
N = 13 (13/0) |
20 | athletes | 12 | 60 | 3.4 mg/kg | Capsule | AOP (RT) →; AOP (AC) → |
| Razazan et al. (36) | RCT crossover |
N = 12 (12/0) |
17 | athletes | 48 | 60 | 3 mg/kg | Capsule | Stroop Test (RT) → ; Stroop Test (AC) → |
| Romdhani et al. (37) | RCT crossover |
N = 14 (14/0) |
19.8 | athletes | NR | 30 | 5 mg/kg | Capsule | SRT (RT) →; CRT (RT) → |
| Smith et al. (38) | RCT crossover |
N = 25 (6/19) |
19 | ordinary people | 15.5 | 25 | 2 mg/kg | Liquid | FAT (RT) →; CST (RT) ↑; SRT (RT) ↑; RDDT (AC) ↑ |
| Yuan et al. (16) | RCT |
N = 40 (0/40) |
19.3 | ordinary people | NR | 65 | 3.6 mg/kg | Capsule | 3-back task (AC) ↑; 3-back task (RT) →; Stroop Test (AC) →; Stroop Test (RT) →; MOST (AC) →; MOST (RT) → |
| Zhang et al. (14) | RCT crossover |
N = 10 (10/0) |
20 | ordinary people | 24 | 60 | 6 mg/kg | Capsule | Stroop Test (RT) ↑; Stroop Test (AC) → |
AC, accuracy; AOP, auditory oddball paradigm; CAT, coincidence anticipation timing; CRT, choice reaction time; CST, categoric search task; DS, digit span WAIS subtest; FAT, focused attention task; MOST, more-odd shifting task; MRT, mental rotation test; NR, not reported; RCT, randomized controlled trial; RDDT, repeated digits detection task; RT, reaction time; SRT, simple reaction time. ↑, indicates significant improvement in the outcome measures; →, indicates no significant improvement.